* xvasprintf.c: New file.
[official-gcc.git] / gcc / tree.def
blobe4625d0982203efd8efcb80c1d93ab98fd15890f
1 /* This file contains the definitions and documentation for the
2 tree codes used in GCC.
3 Copyright (C) 1987-2014 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 3, or (at your option) any later
10 version.
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
22 /* For tcc_references, tcc_expression, tcc_comparison, tcc_unary,
23 tcc_binary, and tcc_statement nodes, which use struct tree_exp, the
24 4th element is the number of argument slots to allocate. This
25 determines the size of the tree node object. Other nodes use
26 different structures, and the size is determined by the tree_union
27 member structure; the 4th element should be zero. Languages that
28 define language-specific tcc_exceptional or tcc_constant codes must
29 define the tree_size langhook to say how big they are.
31 These tree codes have been sorted so that the macros in tree.h that
32 check for various tree codes are optimized into range checks. This
33 gives a measurable performance improvement. When adding a new
34 code, consider its placement in relation to the other codes.
36 When adding a new tree code which might appear as GIMPLE_ASSIGN RHS
37 code, proper handler in chkp_compute_bounds_for_assignment may
38 be required. */
40 /* Any erroneous construct is parsed into a node of this type.
41 This type of node is accepted without complaint in all contexts
42 by later parsing activities, to avoid multiple error messages
43 for one error.
44 No fields in these nodes are used except the TREE_CODE. */
45 DEFTREECODE (ERROR_MARK, "error_mark", tcc_exceptional, 0)
47 /* Used to represent a name (such as, in the DECL_NAME of a decl node).
48 Internally it looks like a STRING_CST node.
49 There is only one IDENTIFIER_NODE ever made for any particular name.
50 Use `get_identifier' to get it (or create it, the first time). */
51 DEFTREECODE (IDENTIFIER_NODE, "identifier_node", tcc_exceptional, 0)
53 /* Has the TREE_VALUE and TREE_PURPOSE fields. */
54 /* These nodes are made into lists by chaining through the
55 TREE_CHAIN field. The elements of the list live in the
56 TREE_VALUE fields, while TREE_PURPOSE fields are occasionally
57 used as well to get the effect of Lisp association lists. */
58 DEFTREECODE (TREE_LIST, "tree_list", tcc_exceptional, 0)
60 /* These nodes contain an array of tree nodes. */
61 DEFTREECODE (TREE_VEC, "tree_vec", tcc_exceptional, 0)
63 /* A symbol binding block. These are arranged in a tree,
64 where the BLOCK_SUBBLOCKS field contains a chain of subblocks
65 chained through the BLOCK_CHAIN field.
66 BLOCK_SUPERCONTEXT points to the parent block.
67 For a block which represents the outermost scope of a function, it
68 points to the FUNCTION_DECL node.
69 BLOCK_VARS points to a chain of decl nodes.
70 BLOCK_CHAIN points to the next BLOCK at the same level.
71 BLOCK_ABSTRACT_ORIGIN points to the original (abstract) tree node which
72 this block is an instance of, or else is NULL to indicate that this
73 block is not an instance of anything else. When non-NULL, the value
74 could either point to another BLOCK node or it could point to a
75 FUNCTION_DECL node (e.g. in the case of a block representing the
76 outermost scope of a particular inlining of a function).
77 BLOCK_ABSTRACT is nonzero if the block represents an abstract
78 instance of a block (i.e. one which is nested within an abstract
79 instance of an inline function).
80 TREE_ASM_WRITTEN is nonzero if the block was actually referenced
81 in the generated assembly. */
82 DEFTREECODE (BLOCK, "block", tcc_exceptional, 0)
84 /* Each data type is represented by a tree node whose code is one of
85 the following: */
86 /* Each node that represents a data type has a component TYPE_SIZE
87 containing a tree that is an expression for the size in bits.
88 The TYPE_MODE contains the machine mode for values of this type.
89 The TYPE_POINTER_TO field contains a type for a pointer to this type,
90 or zero if no such has been created yet.
91 The TYPE_NEXT_VARIANT field is used to chain together types
92 that are variants made by type modifiers such as "const" and "volatile".
93 The TYPE_MAIN_VARIANT field, in any member of such a chain,
94 points to the start of the chain.
95 The TYPE_NAME field contains info on the name used in the program
96 for this type (for GDB symbol table output). It is either a
97 TYPE_DECL node, for types that are typedefs, or an IDENTIFIER_NODE
98 in the case of structs, unions or enums that are known with a tag,
99 or zero for types that have no special name.
100 The TYPE_CONTEXT for any sort of type which could have a name or
101 which could have named members (e.g. tagged types in C/C++) will
102 point to the node which represents the scope of the given type, or
103 will be NULL_TREE if the type has "file scope". For most types, this
104 will point to a BLOCK node or a FUNCTION_DECL node, but it could also
105 point to a FUNCTION_TYPE node (for types whose scope is limited to the
106 formal parameter list of some function type specification) or it
107 could point to a RECORD_TYPE, UNION_TYPE or QUAL_UNION_TYPE node
108 (for C++ "member" types).
109 For non-tagged-types, TYPE_CONTEXT need not be set to anything in
110 particular, since any type which is of some type category (e.g.
111 an array type or a function type) which cannot either have a name
112 itself or have named members doesn't really have a "scope" per se.
113 The TREE_CHAIN field is used as a forward-references to names for
114 ENUMERAL_TYPE, RECORD_TYPE, UNION_TYPE, and QUAL_UNION_TYPE nodes;
115 see below. */
117 /* The ordering of the following codes is optimized for the checking
118 macros in tree.h. Changing the order will degrade the speed of the
119 compiler. OFFSET_TYPE, ENUMERAL_TYPE, BOOLEAN_TYPE, INTEGER_TYPE,
120 REAL_TYPE, POINTER_TYPE. */
122 /* An offset is a pointer relative to an object.
123 The TREE_TYPE field is the type of the object at the offset.
124 The TYPE_OFFSET_BASETYPE points to the node for the type of object
125 that the offset is relative to. */
126 DEFTREECODE (OFFSET_TYPE, "offset_type", tcc_type, 0)
128 /* C enums. The type node looks just like an INTEGER_TYPE node.
129 The symbols for the values of the enum type are defined by
130 CONST_DECL nodes, but the type does not point to them;
131 however, the TYPE_VALUES is a list in which each element's TREE_PURPOSE
132 is a name and the TREE_VALUE is the value (an INTEGER_CST node). */
133 /* A forward reference `enum foo' when no enum named foo is defined yet
134 has zero (a null pointer) in its TYPE_SIZE. The tag name is in
135 the TYPE_NAME field. If the type is later defined, the normal
136 fields are filled in.
137 RECORD_TYPE, UNION_TYPE, and QUAL_UNION_TYPE forward refs are
138 treated similarly. */
139 DEFTREECODE (ENUMERAL_TYPE, "enumeral_type", tcc_type, 0)
141 /* Boolean type (true or false are the only values). Looks like an
142 INTEGRAL_TYPE. */
143 DEFTREECODE (BOOLEAN_TYPE, "boolean_type", tcc_type, 0)
145 /* Integer types in all languages, including char in C.
146 Also used for sub-ranges of other discrete types.
147 Has components TYPE_MIN_VALUE, TYPE_MAX_VALUE (expressions, inclusive)
148 and TYPE_PRECISION (number of bits used by this type).
149 In the case of a subrange type in Pascal, the TREE_TYPE
150 of this will point at the supertype (another INTEGER_TYPE,
151 or an ENUMERAL_TYPE or BOOLEAN_TYPE).
152 Otherwise, the TREE_TYPE is zero. */
153 DEFTREECODE (INTEGER_TYPE, "integer_type", tcc_type, 0)
155 /* C's float and double. Different floating types are distinguished
156 by machine mode and by the TYPE_SIZE and the TYPE_PRECISION. */
157 DEFTREECODE (REAL_TYPE, "real_type", tcc_type, 0)
159 /* The ordering of the following codes is optimized for the checking
160 macros in tree.h. Changing the order will degrade the speed of the
161 compiler. POINTER_TYPE, REFERENCE_TYPE. Note that this range
162 overlaps the previous range of ordered types. */
164 /* All pointer-to-x types have code POINTER_TYPE.
165 The TREE_TYPE points to the node for the type pointed to. */
166 DEFTREECODE (POINTER_TYPE, "pointer_type", tcc_type, 0)
168 /* A reference is like a pointer except that it is coerced
169 automatically to the value it points to. Used in C++. */
170 DEFTREECODE (REFERENCE_TYPE, "reference_type", tcc_type, 0)
172 /* The C++ decltype(nullptr) type. */
173 DEFTREECODE (NULLPTR_TYPE, "nullptr_type", tcc_type, 0)
175 /* _Fract and _Accum types in Embedded-C. Different fixed-point types
176 are distinguished by machine mode and by the TYPE_SIZE and the
177 TYPE_PRECISION. */
178 DEFTREECODE (FIXED_POINT_TYPE, "fixed_point_type", tcc_type, 0)
180 /* The ordering of the following codes is optimized for the checking
181 macros in tree.h. Changing the order will degrade the speed of the
182 compiler. COMPLEX_TYPE, VECTOR_TYPE, ARRAY_TYPE. */
184 /* Complex number types. The TREE_TYPE field is the data type
185 of the real and imaginary parts. It must be of scalar
186 arithmetic type, not including pointer type. */
187 DEFTREECODE (COMPLEX_TYPE, "complex_type", tcc_type, 0)
189 /* Vector types. The TREE_TYPE field is the data type of the vector
190 elements. The TYPE_PRECISION field is the number of subparts of
191 the vector. */
192 DEFTREECODE (VECTOR_TYPE, "vector_type", tcc_type, 0)
194 /* The ordering of the following codes is optimized for the checking
195 macros in tree.h. Changing the order will degrade the speed of the
196 compiler. ARRAY_TYPE, RECORD_TYPE, UNION_TYPE, QUAL_UNION_TYPE.
197 Note that this range overlaps the previous range. */
199 /* Types of arrays. Special fields:
200 TREE_TYPE Type of an array element.
201 TYPE_DOMAIN Type to index by.
202 Its range of values specifies the array length.
203 The field TYPE_POINTER_TO (TREE_TYPE (array_type)) is always nonzero
204 and holds the type to coerce a value of that array type to in C.
205 TYPE_STRING_FLAG indicates a string (in contrast to an array of chars)
206 in languages (such as Chill) that make a distinction. */
207 /* Array types in C or Pascal */
208 DEFTREECODE (ARRAY_TYPE, "array_type", tcc_type, 0)
210 /* Struct in C, or record in Pascal. */
211 /* Special fields:
212 TYPE_FIELDS chain of FIELD_DECLs for the fields of the struct,
213 and VAR_DECLs, TYPE_DECLs and CONST_DECLs for record-scope variables,
214 types and enumerators.
215 A few may need to be added for Pascal. */
216 /* See the comment above, before ENUMERAL_TYPE, for how
217 forward references to struct tags are handled in C. */
218 DEFTREECODE (RECORD_TYPE, "record_type", tcc_type, 0)
220 /* Union in C. Like a struct, except that the offsets of the fields
221 will all be zero. */
222 /* See the comment above, before ENUMERAL_TYPE, for how
223 forward references to union tags are handled in C. */
224 DEFTREECODE (UNION_TYPE, "union_type", tcc_type, 0) /* C union type */
226 /* Similar to UNION_TYPE, except that the expressions in DECL_QUALIFIER
227 in each FIELD_DECL determine what the union contains. The first
228 field whose DECL_QUALIFIER expression is true is deemed to occupy
229 the union. */
230 DEFTREECODE (QUAL_UNION_TYPE, "qual_union_type", tcc_type, 0)
232 /* The ordering of the following codes is optimized for the checking
233 macros in tree.h. Changing the order will degrade the speed of the
234 compiler. VOID_TYPE, FUNCTION_TYPE, METHOD_TYPE. */
236 /* The void type in C */
237 DEFTREECODE (VOID_TYPE, "void_type", tcc_type, 0)
239 /* Type to hold bounds for a pointer.
240 Has TYPE_PRECISION component to specify number of bits used
241 by this type. */
242 DEFTREECODE (POINTER_BOUNDS_TYPE, "pointer_bounds_type", tcc_type, 0)
244 /* Type of functions. Special fields:
245 TREE_TYPE type of value returned.
246 TYPE_ARG_TYPES list of types of arguments expected.
247 this list is made of TREE_LIST nodes.
248 Types of "Procedures" in languages where they are different from functions
249 have code FUNCTION_TYPE also, but then TREE_TYPE is zero or void type. */
250 DEFTREECODE (FUNCTION_TYPE, "function_type", tcc_type, 0)
252 /* METHOD_TYPE is the type of a function which takes an extra first
253 argument for "self", which is not present in the declared argument list.
254 The TREE_TYPE is the return type of the method. The TYPE_METHOD_BASETYPE
255 is the type of "self". TYPE_ARG_TYPES is the real argument list, which
256 includes the hidden argument for "self". */
257 DEFTREECODE (METHOD_TYPE, "method_type", tcc_type, 0)
259 /* This is a language-specific kind of type.
260 Its meaning is defined by the language front end.
261 layout_type does not know how to lay this out,
262 so the front-end must do so manually. */
263 DEFTREECODE (LANG_TYPE, "lang_type", tcc_type, 0)
265 /* Expressions */
267 /* First, the constants. */
269 DEFTREECODE (VOID_CST, "void_cst", tcc_constant, 0)
271 /* Contents are in an array of HOST_WIDE_INTs.
273 We often access these constants both in their native precision and
274 in wider precisions (with the constant being implicitly extended
275 according to TYPE_SIGN). In each case, the useful part of the array
276 may be as wide as the precision requires but may be shorter when all
277 of the upper bits are sign bits. The length of the array when accessed
278 in the constant's native precision is given by TREE_INT_CST_NUNITS.
279 The length of the array when accessed in wider precisions is given
280 by TREE_INT_CST_EXT_NUNITS. Each element can be obtained using
281 TREE_INT_CST_ELT.
283 INTEGER_CST nodes can be shared, and therefore should be considered
284 read only. They should be copied before setting a flag such as
285 TREE_OVERFLOW. If an INTEGER_CST has TREE_OVERFLOW already set,
286 it is known to be unique. INTEGER_CST nodes are created for the
287 integral types, for pointer types and for vector and float types in
288 some circumstances. */
289 DEFTREECODE (INTEGER_CST, "integer_cst", tcc_constant, 0)
291 /* Contents are in TREE_REAL_CST field. */
292 DEFTREECODE (REAL_CST, "real_cst", tcc_constant, 0)
294 /* Contents are in TREE_FIXED_CST field. */
295 DEFTREECODE (FIXED_CST, "fixed_cst", tcc_constant, 0)
297 /* Contents are in TREE_REALPART and TREE_IMAGPART fields,
298 whose contents are other constant nodes. */
299 DEFTREECODE (COMPLEX_CST, "complex_cst", tcc_constant, 0)
301 /* Contents are in TREE_VECTOR_CST_ELTS field. */
302 DEFTREECODE (VECTOR_CST, "vector_cst", tcc_constant, 0)
304 /* Contents are TREE_STRING_LENGTH and the actual contents of the string. */
305 DEFTREECODE (STRING_CST, "string_cst", tcc_constant, 0)
307 /* Declarations. All references to names are represented as ..._DECL
308 nodes. The decls in one binding context are chained through the
309 TREE_CHAIN field. Each DECL has a DECL_NAME field which contains
310 an IDENTIFIER_NODE. (Some decls, most often labels, may have zero
311 as the DECL_NAME). DECL_CONTEXT points to the node representing
312 the context in which this declaration has its scope. For
313 FIELD_DECLs, this is the RECORD_TYPE, UNION_TYPE, or
314 QUAL_UNION_TYPE node that the field is a member of. For VAR_DECL,
315 PARM_DECL, FUNCTION_DECL, LABEL_DECL, and CONST_DECL nodes, this
316 points to either the FUNCTION_DECL for the containing function, the
317 RECORD_TYPE or UNION_TYPE for the containing type, or NULL_TREE or
318 a TRANSLATION_UNIT_DECL if the given decl has "file scope".
319 DECL_ABSTRACT_ORIGIN, if non-NULL, points to the original (abstract)
320 ..._DECL node of which this decl is an (inlined or template expanded)
321 instance.
322 The TREE_TYPE field holds the data type of the object, when relevant.
323 LABEL_DECLs have no data type. For TYPE_DECL, the TREE_TYPE field
324 contents are the type whose name is being declared.
325 The DECL_ALIGN, DECL_SIZE,
326 and DECL_MODE fields exist in decl nodes just as in type nodes.
327 They are unused in LABEL_DECL, TYPE_DECL and CONST_DECL nodes.
329 DECL_FIELD_BIT_OFFSET holds an integer number of bits offset for
330 the location. DECL_VOFFSET holds an expression for a variable
331 offset; it is to be multiplied by DECL_VOFFSET_UNIT (an integer).
332 These fields are relevant only in FIELD_DECLs and PARM_DECLs.
334 DECL_INITIAL holds the value to initialize a variable to,
335 or the value of a constant. For a function, it holds the body
336 (a node of type BLOCK representing the function's binding contour
337 and whose body contains the function's statements.) For a LABEL_DECL
338 in C, it is a flag, nonzero if the label's definition has been seen.
340 PARM_DECLs use a special field:
341 DECL_ARG_TYPE is the type in which the argument is actually
342 passed, which may be different from its type within the function.
344 FUNCTION_DECLs use four special fields:
345 DECL_ARGUMENTS holds a chain of PARM_DECL nodes for the arguments.
346 DECL_RESULT holds a RESULT_DECL node for the value of a function.
347 The DECL_RTL field is 0 for a function that returns no value.
348 (C functions returning void have zero here.)
349 The TREE_TYPE field is the type in which the result is actually
350 returned. This is usually the same as the return type of the
351 FUNCTION_DECL, but it may be a wider integer type because of
352 promotion.
353 DECL_FUNCTION_CODE is a code number that is nonzero for
354 built-in functions. Its value is an enum built_in_function
355 that says which built-in function it is.
357 DECL_SOURCE_FILE holds a filename string and DECL_SOURCE_LINE
358 holds a line number. In some cases these can be the location of
359 a reference, if no definition has been seen.
361 DECL_ABSTRACT is nonzero if the decl represents an abstract instance
362 of a decl (i.e. one which is nested within an abstract instance of a
363 inline function. */
365 DEFTREECODE (FUNCTION_DECL, "function_decl", tcc_declaration, 0)
366 DEFTREECODE (LABEL_DECL, "label_decl", tcc_declaration, 0)
367 /* The ordering of the following codes is optimized for the checking
368 macros in tree.h. Changing the order will degrade the speed of the
369 compiler. FIELD_DECL, VAR_DECL, CONST_DECL, PARM_DECL,
370 TYPE_DECL. */
371 DEFTREECODE (FIELD_DECL, "field_decl", tcc_declaration, 0)
372 DEFTREECODE (VAR_DECL, "var_decl", tcc_declaration, 0)
373 DEFTREECODE (CONST_DECL, "const_decl", tcc_declaration, 0)
374 DEFTREECODE (PARM_DECL, "parm_decl", tcc_declaration, 0)
375 DEFTREECODE (TYPE_DECL, "type_decl", tcc_declaration, 0)
376 DEFTREECODE (RESULT_DECL, "result_decl", tcc_declaration, 0)
378 /* A "declaration" of a debug temporary. It should only appear in
379 DEBUG stmts. */
380 DEFTREECODE (DEBUG_EXPR_DECL, "debug_expr_decl", tcc_declaration, 0)
382 /* A namespace declaration. Namespaces appear in DECL_CONTEXT of other
383 _DECLs, providing a hierarchy of names. */
384 DEFTREECODE (NAMESPACE_DECL, "namespace_decl", tcc_declaration, 0)
386 /* A declaration import.
387 The C++ FE uses this to represent a using-directive; eg:
388 "using namespace foo".
389 But it could be used to represent any declaration import construct.
390 Whenever a declaration import appears in a lexical block, the BLOCK node
391 representing that lexical block in GIMPLE will contain an IMPORTED_DECL
392 node, linked via BLOCK_VARS accessor of the said BLOCK.
393 For a given NODE which code is IMPORTED_DECL,
394 IMPORTED_DECL_ASSOCIATED_DECL (NODE) accesses the imported declaration. */
395 DEFTREECODE (IMPORTED_DECL, "imported_decl", tcc_declaration, 0)
397 /* A namelist declaration.
398 The Fortran FE uses this to represent a namelist statement, e.g.:
399 NAMELIST /namelist-group-name/ namelist-group-object-list.
400 Whenever a declaration import appears in a lexical block, the BLOCK node
401 representing that lexical block in GIMPLE will contain an NAMELIST_DECL
402 node, linked via BLOCK_VARS accessor of the said BLOCK.
403 For a given NODE which code is NAMELIST_DECL,
404 NAMELIST_DECL_ASSOCIATED_DECL (NODE) accesses the imported declaration. */
405 DEFTREECODE (NAMELIST_DECL, "namelist_decl", tcc_declaration, 0)
407 /* A translation unit. This is not technically a declaration, since it
408 can't be looked up, but it's close enough. */
409 DEFTREECODE (TRANSLATION_UNIT_DECL, "translation_unit_decl",\
410 tcc_declaration, 0)
412 /* References to storage. */
414 /* The ordering of the following codes is optimized for the classification
415 in handled_component_p. Keep them in a consecutive group. */
417 /* Value is structure or union component.
418 Operand 0 is the structure or union (an expression).
419 Operand 1 is the field (a node of type FIELD_DECL).
420 Operand 2, if present, is the value of DECL_FIELD_OFFSET, measured
421 in units of DECL_OFFSET_ALIGN / BITS_PER_UNIT. */
422 DEFTREECODE (COMPONENT_REF, "component_ref", tcc_reference, 3)
424 /* Reference to a group of bits within an object. Similar to COMPONENT_REF
425 except the position is given explicitly rather than via a FIELD_DECL.
426 Operand 0 is the structure or union expression;
427 operand 1 is a tree giving the constant number of bits being referenced;
428 operand 2 is a tree giving the constant position of the first referenced bit.
429 The result type width has to match the number of bits referenced.
430 If the result type is integral, its signedness specifies how it is extended
431 to its mode width. */
432 DEFTREECODE (BIT_FIELD_REF, "bit_field_ref", tcc_reference, 3)
434 /* Array indexing.
435 Operand 0 is the array; operand 1 is a (single) array index.
436 Operand 2, if present, is a copy of TYPE_MIN_VALUE of the index.
437 Operand 3, if present, is the element size, measured in units of
438 the alignment of the element type. */
439 DEFTREECODE (ARRAY_REF, "array_ref", tcc_reference, 4)
441 /* Likewise, except that the result is a range ("slice") of the array. The
442 starting index of the resulting array is taken from operand 1 and the size
443 of the range is taken from the type of the expression. */
444 DEFTREECODE (ARRAY_RANGE_REF, "array_range_ref", tcc_reference, 4)
446 /* Used only on an operand of complex type, these return
447 a value of the corresponding component type. */
448 DEFTREECODE (REALPART_EXPR, "realpart_expr", tcc_reference, 1)
449 DEFTREECODE (IMAGPART_EXPR, "imagpart_expr", tcc_reference, 1)
451 /* Represents viewing something of one type as being of a second type.
452 This corresponds to an "Unchecked Conversion" in Ada and roughly to
453 the idiom *(type2 *)&X in C. The only operand is the value to be
454 viewed as being of another type. It is undefined if the type of the
455 input and of the expression have different sizes.
457 This code may also be used within the LHS of a MODIFY_EXPR, in which
458 case no actual data motion may occur. TREE_ADDRESSABLE will be set in
459 this case and GCC must abort if it could not do the operation without
460 generating insns. */
461 DEFTREECODE (VIEW_CONVERT_EXPR, "view_convert_expr", tcc_reference, 1)
463 /* C unary `*' or Pascal `^'. One operand, an expression for a pointer. */
464 DEFTREECODE (INDIRECT_REF, "indirect_ref", tcc_reference, 1)
466 /* Used to represent lookup in a virtual method table which is dependent on
467 the runtime type of an object. Operands are:
468 OBJ_TYPE_REF_EXPR: An expression that evaluates the value to use.
469 OBJ_TYPE_REF_OBJECT: Is the object on whose behalf the lookup is
470 being performed. Through this the optimizers may be able to statically
471 determine the dynamic type of the object.
472 OBJ_TYPE_REF_TOKEN: An integer index to the virtual method table. */
473 DEFTREECODE (OBJ_TYPE_REF, "obj_type_ref", tcc_expression, 3)
475 /* Used to represent the brace-enclosed initializers for a structure or an
476 array. It contains a sequence of component values made out of a VEC of
477 constructor_elt.
479 For RECORD_TYPE, UNION_TYPE, or QUAL_UNION_TYPE:
480 The field INDEX of each constructor_elt is a FIELD_DECL.
482 For ARRAY_TYPE:
483 The field INDEX of each constructor_elt is the corresponding index.
484 If the index is a RANGE_EXPR, it is a short-hand for many nodes,
485 one for each index in the range. (If the corresponding field VALUE
486 has side-effects, they are evaluated once for each element. Wrap the
487 value in a SAVE_EXPR if you want to evaluate side effects only once.)
489 Components that aren't present are cleared as per the C semantics,
490 unless the CONSTRUCTOR_NO_CLEARING flag is set, in which case their
491 value becomes undefined. */
492 DEFTREECODE (CONSTRUCTOR, "constructor", tcc_exceptional, 0)
494 /* The expression types are mostly straightforward, with the fourth argument
495 of DEFTREECODE saying how many operands there are.
496 Unless otherwise specified, the operands are expressions and the
497 types of all the operands and the expression must all be the same. */
499 /* Contains two expressions to compute, one followed by the other.
500 the first value is ignored. The second one's value is used. The
501 type of the first expression need not agree with the other types. */
502 DEFTREECODE (COMPOUND_EXPR, "compound_expr", tcc_expression, 2)
504 /* Assignment expression. Operand 0 is the what to set; 1, the new value. */
505 DEFTREECODE (MODIFY_EXPR, "modify_expr", tcc_expression, 2)
507 /* Initialization expression. Operand 0 is the variable to initialize;
508 Operand 1 is the initializer. This differs from MODIFY_EXPR in that any
509 reference to the referent of operand 0 within operand 1 is undefined. */
510 DEFTREECODE (INIT_EXPR, "init_expr", tcc_expression, 2)
512 /* For TARGET_EXPR, operand 0 is the target of an initialization,
513 operand 1 is the initializer for the target, which may be void
514 if simply expanding it initializes the target.
515 operand 2 is the cleanup for this node, if any.
516 operand 3 is the saved initializer after this node has been
517 expanded once; this is so we can re-expand the tree later. */
518 DEFTREECODE (TARGET_EXPR, "target_expr", tcc_expression, 4)
520 /* Conditional expression ( ... ? ... : ... in C).
521 Operand 0 is the condition.
522 Operand 1 is the then-value.
523 Operand 2 is the else-value.
524 Operand 0 may be of any type.
525 Operand 1 must have the same type as the entire expression, unless
526 it unconditionally throws an exception, in which case it should
527 have VOID_TYPE. The same constraints apply to operand 2. The
528 condition in operand 0 must be of integral type.
530 In cfg gimple, if you do not have a selection expression, operands
531 1 and 2 are NULL. The operands are then taken from the cfg edges. */
532 DEFTREECODE (COND_EXPR, "cond_expr", tcc_expression, 3)
534 /* Vector conditional expression. It is like COND_EXPR, but with
535 vector operands.
537 A = VEC_COND_EXPR ( X < Y, B, C)
539 means
541 for (i=0; i<N; i++)
542 A[i] = X[i] < Y[i] ? B[i] : C[i];
544 DEFTREECODE (VEC_COND_EXPR, "vec_cond_expr", tcc_expression, 3)
546 /* Vector permutation expression. A = VEC_PERM_EXPR<v0, v1, mask> means
548 N = length(mask)
549 foreach i in N:
550 M = mask[i] % (2*N)
551 A = M < N ? v0[M] : v1[M-N]
553 V0 and V1 are vectors of the same type. MASK is an integer-typed
554 vector. The number of MASK elements must be the same with the
555 number of elements in V0 and V1. The size of the inner type
556 of the MASK and of the V0 and V1 must be the same.
558 DEFTREECODE (VEC_PERM_EXPR, "vec_perm_expr", tcc_expression, 3)
560 /* Declare local variables, including making RTL and allocating space.
561 BIND_EXPR_VARS is a chain of VAR_DECL nodes for the variables.
562 BIND_EXPR_BODY is the body, the expression to be computed using
563 the variables. The value of operand 1 becomes that of the BIND_EXPR.
564 BIND_EXPR_BLOCK is the BLOCK that corresponds to these bindings
565 for debugging purposes. If this BIND_EXPR is actually expanded,
566 that sets the TREE_USED flag in the BLOCK.
568 The BIND_EXPR is not responsible for informing parsers
569 about these variables. If the body is coming from the input file,
570 then the code that creates the BIND_EXPR is also responsible for
571 informing the parser of the variables.
573 If the BIND_EXPR is ever expanded, its TREE_USED flag is set.
574 This tells the code for debugging symbol tables not to ignore the BIND_EXPR.
575 If the BIND_EXPR should be output for debugging but will not be expanded,
576 set the TREE_USED flag by hand.
578 In order for the BIND_EXPR to be known at all, the code that creates it
579 must also install it as a subblock in the tree of BLOCK
580 nodes for the function. */
581 DEFTREECODE (BIND_EXPR, "bind_expr", tcc_expression, 3)
583 /* Function call. CALL_EXPRs are represented by variably-sized expression
584 nodes. There are at least three fixed operands. Operand 0 is an
585 INTEGER_CST node containing the total operand count, the number of
586 arguments plus 3. Operand 1 is the function or NULL, while operand 2 is
587 is static chain argument, or NULL. The remaining operands are the
588 arguments to the call. */
589 DEFTREECODE (CALL_EXPR, "call_expr", tcc_vl_exp, 3)
591 /* Specify a value to compute along with its corresponding cleanup.
592 Operand 0 is the cleanup expression.
593 The cleanup is executed by the first enclosing CLEANUP_POINT_EXPR,
594 which must exist. This differs from TRY_CATCH_EXPR in that operand 1
595 is always evaluated when cleanups are run. */
596 DEFTREECODE (WITH_CLEANUP_EXPR, "with_cleanup_expr", tcc_expression, 1)
598 /* Specify a cleanup point.
599 Operand 0 is an expression that may have cleanups. If it does, those
600 cleanups are executed after the expression is expanded.
602 Note that if the expression is a reference to storage, it is forced out
603 of memory before the cleanups are run. This is necessary to handle
604 cases where the cleanups modify the storage referenced; in the
605 expression 't.i', if 't' is a struct with an integer member 'i' and a
606 cleanup which modifies 'i', the value of the expression depends on
607 whether the cleanup is run before or after 't.i' is evaluated. When
608 expand_expr is run on 't.i', it returns a MEM. This is not good enough;
609 the value of 't.i' must be forced out of memory.
611 As a consequence, the operand of a CLEANUP_POINT_EXPR must not have
612 BLKmode, because it will not be forced out of memory. */
613 DEFTREECODE (CLEANUP_POINT_EXPR, "cleanup_point_expr", tcc_expression, 1)
615 /* The following code is used in languages that have types where some
616 field in an object of the type contains a value that is used in the
617 computation of another field's offset or size and/or the size of the
618 type. The positions and/or sizes of fields can vary from object to
619 object of the same type or even for one and the same object within
620 its scope.
622 Record types with discriminants in Ada or schema types in Pascal are
623 examples of such types. This mechanism is also used to create "fat
624 pointers" for unconstrained array types in Ada; the fat pointer is a
625 structure one of whose fields is a pointer to the actual array type
626 and the other field is a pointer to a template, which is a structure
627 containing the bounds of the array. The bounds in the type pointed
628 to by the first field in the fat pointer refer to the values in the
629 template.
631 When you wish to construct such a type you need "self-references"
632 that allow you to reference the object having this type from the
633 TYPE node, i.e. without having a variable instantiating this type.
635 Such a "self-references" is done using a PLACEHOLDER_EXPR. This is
636 a node that will later be replaced with the object being referenced.
637 Its type is that of the object and selects which object to use from
638 a chain of references (see below). No other slots are used in the
639 PLACEHOLDER_EXPR.
641 For example, if your type FOO is a RECORD_TYPE with a field BAR,
642 and you need the value of <variable>.BAR to calculate TYPE_SIZE
643 (FOO), just substitute <variable> above with a PLACEHOLDER_EXPR
644 whose TREE_TYPE is FOO. Then construct your COMPONENT_REF with
645 the PLACEHOLDER_EXPR as the first operand (which has the correct
646 type). Later, when the size is needed in the program, the back-end
647 will find this PLACEHOLDER_EXPR and generate code to calculate the
648 actual size at run-time. In the following, we describe how this
649 calculation is done.
651 When we wish to evaluate a size or offset, we check whether it contains a
652 PLACEHOLDER_EXPR. If it does, we call substitute_placeholder_in_expr
653 passing both that tree and an expression within which the object may be
654 found. The latter expression is the object itself in the simple case of
655 an Ada record with discriminant, but it can be the array in the case of an
656 unconstrained array.
658 In the latter case, we need the fat pointer, because the bounds of
659 the array can only be accessed from it. However, we rely here on the
660 fact that the expression for the array contains the dereference of
661 the fat pointer that obtained the array pointer. */
663 /* Denotes a record to later be substituted before evaluating this expression.
664 The type of this expression is used to find the record to replace it. */
665 DEFTREECODE (PLACEHOLDER_EXPR, "placeholder_expr", tcc_exceptional, 0)
667 /* Simple arithmetic. */
668 DEFTREECODE (PLUS_EXPR, "plus_expr", tcc_binary, 2)
669 DEFTREECODE (MINUS_EXPR, "minus_expr", tcc_binary, 2)
670 DEFTREECODE (MULT_EXPR, "mult_expr", tcc_binary, 2)
672 /* Pointer addition. The first operand is always a pointer and the
673 second operand is an integer of type sizetype. */
674 DEFTREECODE (POINTER_PLUS_EXPR, "pointer_plus_expr", tcc_binary, 2)
676 /* Highpart multiplication. For an integral type with precision B,
677 returns bits [2B-1, B] of the full 2*B product. */
678 DEFTREECODE (MULT_HIGHPART_EXPR, "mult_highpart_expr", tcc_binary, 2)
680 /* Division for integer result that rounds the quotient toward zero. */
681 DEFTREECODE (TRUNC_DIV_EXPR, "trunc_div_expr", tcc_binary, 2)
683 /* Division for integer result that rounds the quotient toward infinity. */
684 DEFTREECODE (CEIL_DIV_EXPR, "ceil_div_expr", tcc_binary, 2)
686 /* Division for integer result that rounds toward minus infinity. */
687 DEFTREECODE (FLOOR_DIV_EXPR, "floor_div_expr", tcc_binary, 2)
689 /* Division for integer result that rounds toward nearest integer. */
690 DEFTREECODE (ROUND_DIV_EXPR, "round_div_expr", tcc_binary, 2)
692 /* Four kinds of remainder that go with the four kinds of division. */
693 DEFTREECODE (TRUNC_MOD_EXPR, "trunc_mod_expr", tcc_binary, 2)
694 DEFTREECODE (CEIL_MOD_EXPR, "ceil_mod_expr", tcc_binary, 2)
695 DEFTREECODE (FLOOR_MOD_EXPR, "floor_mod_expr", tcc_binary, 2)
696 DEFTREECODE (ROUND_MOD_EXPR, "round_mod_expr", tcc_binary, 2)
698 /* Division for real result. */
699 DEFTREECODE (RDIV_EXPR, "rdiv_expr", tcc_binary, 2)
701 /* Division which is not supposed to need rounding.
702 Used for pointer subtraction in C. */
703 DEFTREECODE (EXACT_DIV_EXPR, "exact_div_expr", tcc_binary, 2)
705 /* Conversion of real to fixed point by truncation. */
706 DEFTREECODE (FIX_TRUNC_EXPR, "fix_trunc_expr", tcc_unary, 1)
708 /* Conversion of an integer to a real. */
709 DEFTREECODE (FLOAT_EXPR, "float_expr", tcc_unary, 1)
711 /* Unary negation. */
712 DEFTREECODE (NEGATE_EXPR, "negate_expr", tcc_unary, 1)
714 /* Minimum and maximum values. When used with floating point, if both
715 operands are zeros, or if either operand is NaN, then it is unspecified
716 which of the two operands is returned as the result. */
717 DEFTREECODE (MIN_EXPR, "min_expr", tcc_binary, 2)
718 DEFTREECODE (MAX_EXPR, "max_expr", tcc_binary, 2)
720 /* Represents the absolute value of the operand.
722 An ABS_EXPR must have either an INTEGER_TYPE or a REAL_TYPE. The
723 operand of the ABS_EXPR must have the same type. */
724 DEFTREECODE (ABS_EXPR, "abs_expr", tcc_unary, 1)
726 /* Shift operations for shift and rotate.
727 Shift means logical shift if done on an
728 unsigned type, arithmetic shift if done on a signed type.
729 The second operand is the number of bits to
730 shift by; it need not be the same type as the first operand and result.
731 Note that the result is undefined if the second operand is larger
732 than or equal to the first operand's type size.
734 The first operand of a shift can have either an integer or a
735 (non-integer) fixed-point type. We follow the ISO/IEC TR 18037:2004
736 semantics for the latter.
738 Rotates are defined for integer types only. */
739 DEFTREECODE (LSHIFT_EXPR, "lshift_expr", tcc_binary, 2)
740 DEFTREECODE (RSHIFT_EXPR, "rshift_expr", tcc_binary, 2)
741 DEFTREECODE (LROTATE_EXPR, "lrotate_expr", tcc_binary, 2)
742 DEFTREECODE (RROTATE_EXPR, "rrotate_expr", tcc_binary, 2)
744 /* Bitwise operations. Operands have same mode as result. */
745 DEFTREECODE (BIT_IOR_EXPR, "bit_ior_expr", tcc_binary, 2)
746 DEFTREECODE (BIT_XOR_EXPR, "bit_xor_expr", tcc_binary, 2)
747 DEFTREECODE (BIT_AND_EXPR, "bit_and_expr", tcc_binary, 2)
748 DEFTREECODE (BIT_NOT_EXPR, "bit_not_expr", tcc_unary, 1)
750 /* ANDIF and ORIF allow the second operand not to be computed if the
751 value of the expression is determined from the first operand. AND,
752 OR, and XOR always compute the second operand whether its value is
753 needed or not (for side effects). The operand may have
754 BOOLEAN_TYPE or INTEGER_TYPE. In either case, the argument will be
755 either zero or one. For example, a TRUTH_NOT_EXPR will never have
756 an INTEGER_TYPE VAR_DECL as its argument; instead, a NE_EXPR will be
757 used to compare the VAR_DECL to zero, thereby obtaining a node with
758 value zero or one. */
759 DEFTREECODE (TRUTH_ANDIF_EXPR, "truth_andif_expr", tcc_expression, 2)
760 DEFTREECODE (TRUTH_ORIF_EXPR, "truth_orif_expr", tcc_expression, 2)
761 DEFTREECODE (TRUTH_AND_EXPR, "truth_and_expr", tcc_expression, 2)
762 DEFTREECODE (TRUTH_OR_EXPR, "truth_or_expr", tcc_expression, 2)
763 DEFTREECODE (TRUTH_XOR_EXPR, "truth_xor_expr", tcc_expression, 2)
764 DEFTREECODE (TRUTH_NOT_EXPR, "truth_not_expr", tcc_expression, 1)
766 /* Relational operators.
767 `EQ_EXPR' and `NE_EXPR' are allowed for any types.
768 The others are allowed only for integer (or pointer or enumeral)
769 or real types.
770 In all cases the operands will have the same type,
771 and the value is either the type used by the language for booleans
772 or an integer vector type of the same size and with the same number
773 of elements as the comparison operands. True for a vector of
774 comparison results has all bits set while false is equal to zero. */
775 DEFTREECODE (LT_EXPR, "lt_expr", tcc_comparison, 2)
776 DEFTREECODE (LE_EXPR, "le_expr", tcc_comparison, 2)
777 DEFTREECODE (GT_EXPR, "gt_expr", tcc_comparison, 2)
778 DEFTREECODE (GE_EXPR, "ge_expr", tcc_comparison, 2)
779 DEFTREECODE (EQ_EXPR, "eq_expr", tcc_comparison, 2)
780 DEFTREECODE (NE_EXPR, "ne_expr", tcc_comparison, 2)
782 /* Additional relational operators for floating point unordered. */
783 DEFTREECODE (UNORDERED_EXPR, "unordered_expr", tcc_comparison, 2)
784 DEFTREECODE (ORDERED_EXPR, "ordered_expr", tcc_comparison, 2)
786 /* These are equivalent to unordered or ... */
787 DEFTREECODE (UNLT_EXPR, "unlt_expr", tcc_comparison, 2)
788 DEFTREECODE (UNLE_EXPR, "unle_expr", tcc_comparison, 2)
789 DEFTREECODE (UNGT_EXPR, "ungt_expr", tcc_comparison, 2)
790 DEFTREECODE (UNGE_EXPR, "unge_expr", tcc_comparison, 2)
791 DEFTREECODE (UNEQ_EXPR, "uneq_expr", tcc_comparison, 2)
793 /* This is the reverse of uneq_expr. */
794 DEFTREECODE (LTGT_EXPR, "ltgt_expr", tcc_comparison, 2)
796 DEFTREECODE (RANGE_EXPR, "range_expr", tcc_binary, 2)
798 /* Represents a re-association barrier for floating point expressions
799 like explicit parenthesis in fortran. */
800 DEFTREECODE (PAREN_EXPR, "paren_expr", tcc_unary, 1)
802 /* Represents a conversion of type of a value.
803 All conversions, including implicit ones, must be
804 represented by CONVERT_EXPR or NOP_EXPR nodes. */
805 DEFTREECODE (CONVERT_EXPR, "convert_expr", tcc_unary, 1)
807 /* Conversion of a pointer value to a pointer to a different
808 address space. */
809 DEFTREECODE (ADDR_SPACE_CONVERT_EXPR, "addr_space_convert_expr", tcc_unary, 1)
811 /* Conversion of a fixed-point value to an integer, a real, or a fixed-point
812 value. Or conversion of a fixed-point value from an integer, a real, or
813 a fixed-point value. */
814 DEFTREECODE (FIXED_CONVERT_EXPR, "fixed_convert_expr", tcc_unary, 1)
816 /* Represents a conversion expected to require no code to be generated. */
817 DEFTREECODE (NOP_EXPR, "nop_expr", tcc_unary, 1)
819 /* Value is same as argument, but guaranteed not an lvalue. */
820 DEFTREECODE (NON_LVALUE_EXPR, "non_lvalue_expr", tcc_unary, 1)
822 /* A COMPOUND_LITERAL_EXPR represents a literal that is placed in a DECL. The
823 COMPOUND_LITERAL_EXPR_DECL_EXPR is the a DECL_EXPR containing the decl
824 for the anonymous object represented by the COMPOUND_LITERAL;
825 the DECL_INITIAL of that decl is the CONSTRUCTOR that initializes
826 the compound literal. */
827 DEFTREECODE (COMPOUND_LITERAL_EXPR, "compound_literal_expr", tcc_expression, 1)
829 /* Represents something we computed once and will use multiple times.
830 First operand is that expression. After it is evaluated once, it
831 will be replaced by the temporary variable that holds the value. */
832 DEFTREECODE (SAVE_EXPR, "save_expr", tcc_expression, 1)
834 /* & in C. Value is the address at which the operand's value resides.
835 Operand may have any mode. Result mode is Pmode. */
836 DEFTREECODE (ADDR_EXPR, "addr_expr", tcc_expression, 1)
838 /* Operand0 is a function constant; result is part N of a function
839 descriptor of type ptr_mode. */
840 DEFTREECODE (FDESC_EXPR, "fdesc_expr", tcc_expression, 2)
842 /* Given two real or integer operands of the same type,
843 returns a complex value of the corresponding complex type. */
844 DEFTREECODE (COMPLEX_EXPR, "complex_expr", tcc_binary, 2)
846 /* Complex conjugate of operand. Used only on complex types. */
847 DEFTREECODE (CONJ_EXPR, "conj_expr", tcc_unary, 1)
849 /* Nodes for ++ and -- in C.
850 The second arg is how much to increment or decrement by.
851 For a pointer, it would be the size of the object pointed to. */
852 DEFTREECODE (PREDECREMENT_EXPR, "predecrement_expr", tcc_expression, 2)
853 DEFTREECODE (PREINCREMENT_EXPR, "preincrement_expr", tcc_expression, 2)
854 DEFTREECODE (POSTDECREMENT_EXPR, "postdecrement_expr", tcc_expression, 2)
855 DEFTREECODE (POSTINCREMENT_EXPR, "postincrement_expr", tcc_expression, 2)
857 /* Used to implement `va_arg'. */
858 DEFTREECODE (VA_ARG_EXPR, "va_arg_expr", tcc_expression, 1)
860 /* Evaluate operand 1. If and only if an exception is thrown during
861 the evaluation of operand 1, evaluate operand 2.
863 This differs from TRY_FINALLY_EXPR in that operand 2 is not evaluated
864 on a normal or jump exit, only on an exception. */
865 DEFTREECODE (TRY_CATCH_EXPR, "try_catch_expr", tcc_statement, 2)
867 /* Evaluate the first operand.
868 The second operand is a cleanup expression which is evaluated
869 on any exit (normal, exception, or jump out) from this expression. */
870 DEFTREECODE (TRY_FINALLY_EXPR, "try_finally", tcc_statement, 2)
872 /* These types of expressions have no useful value,
873 and always have side effects. */
875 /* Used to represent a local declaration. The operand is DECL_EXPR_DECL. */
876 DEFTREECODE (DECL_EXPR, "decl_expr", tcc_statement, 1)
878 /* A label definition, encapsulated as a statement.
879 Operand 0 is the LABEL_DECL node for the label that appears here.
880 The type should be void and the value should be ignored. */
881 DEFTREECODE (LABEL_EXPR, "label_expr", tcc_statement, 1)
883 /* GOTO. Operand 0 is a LABEL_DECL node or an expression.
884 The type should be void and the value should be ignored. */
885 DEFTREECODE (GOTO_EXPR, "goto_expr", tcc_statement, 1)
887 /* RETURN. Evaluates operand 0, then returns from the current function.
888 Presumably that operand is an assignment that stores into the
889 RESULT_DECL that hold the value to be returned.
890 The operand may be null.
891 The type should be void and the value should be ignored. */
892 DEFTREECODE (RETURN_EXPR, "return_expr", tcc_statement, 1)
894 /* Exit the inner most loop conditionally. Operand 0 is the condition.
895 The type should be void and the value should be ignored. */
896 DEFTREECODE (EXIT_EXPR, "exit_expr", tcc_statement, 1)
898 /* A loop. Operand 0 is the body of the loop.
899 It must contain an EXIT_EXPR or is an infinite loop.
900 The type should be void and the value should be ignored. */
901 DEFTREECODE (LOOP_EXPR, "loop_expr", tcc_statement, 1)
903 /* Switch expression.
905 TREE_TYPE is the original type of the condition, before any
906 language required type conversions. It may be NULL, in which case
907 the original type and final types are assumed to be the same.
909 Operand 0 is the expression used to perform the branch,
910 Operand 1 is the body of the switch, which probably contains
911 CASE_LABEL_EXPRs. It may also be NULL, in which case operand 2
912 must not be NULL.
913 Operand 2 is either NULL_TREE or a TREE_VEC of the CASE_LABEL_EXPRs
914 of all the cases. */
915 DEFTREECODE (SWITCH_EXPR, "switch_expr", tcc_statement, 3)
917 /* Used to represent a case label.
919 Operand 0 is CASE_LOW. It may be NULL_TREE, in which case the label
920 is a 'default' label.
921 Operand 1 is CASE_HIGH. If it is NULL_TREE, the label is a simple
922 (one-value) case label. If it is non-NULL_TREE, the case is a range.
923 Operand 2 is CASE_LABEL, which is is the corresponding LABEL_DECL.
924 Operand 4 is CASE_CHAIN. This operand is only used in tree-cfg.c to
925 speed up the lookup of case labels which use a particular edge in
926 the control flow graph. */
927 DEFTREECODE (CASE_LABEL_EXPR, "case_label_expr", tcc_statement, 4)
929 /* Used to represent an inline assembly statement. ASM_STRING returns a
930 STRING_CST for the instruction (e.g., "mov x, y"). ASM_OUTPUTS,
931 ASM_INPUTS, and ASM_CLOBBERS represent the outputs, inputs, and clobbers
932 for the statement. ASM_LABELS, if present, indicates various destinations
933 for the asm; labels cannot be combined with outputs. */
934 DEFTREECODE (ASM_EXPR, "asm_expr", tcc_statement, 5)
936 /* Variable references for SSA analysis. New SSA names are created every
937 time a variable is assigned a new value. The SSA builder uses SSA_NAME
938 nodes to implement SSA versioning. */
939 DEFTREECODE (SSA_NAME, "ssa_name", tcc_exceptional, 0)
941 /* Used to represent a typed exception handler. CATCH_TYPES is the type (or
942 list of types) handled, and CATCH_BODY is the code for the handler. */
943 DEFTREECODE (CATCH_EXPR, "catch_expr", tcc_statement, 2)
945 /* Used to represent an exception specification. EH_FILTER_TYPES is a list
946 of allowed types, and EH_FILTER_FAILURE is an expression to evaluate on
947 failure. */
948 DEFTREECODE (EH_FILTER_EXPR, "eh_filter_expr", tcc_statement, 2)
950 /* Node used for describing a property that is known at compile
951 time. */
952 DEFTREECODE (SCEV_KNOWN, "scev_known", tcc_expression, 0)
954 /* Node used for describing a property that is not known at compile
955 time. */
956 DEFTREECODE (SCEV_NOT_KNOWN, "scev_not_known", tcc_expression, 0)
958 /* Polynomial chains of recurrences.
959 Under the form: cr = {CHREC_LEFT (cr), +, CHREC_RIGHT (cr)}. */
960 DEFTREECODE (POLYNOMIAL_CHREC, "polynomial_chrec", tcc_expression, 3)
962 /* Used to chain children of container statements together.
963 Use the interface in tree-iterator.h to access this node. */
964 DEFTREECODE (STATEMENT_LIST, "statement_list", tcc_exceptional, 0)
966 /* Predicate assertion. Artificial expression generated by the optimizers
967 to keep track of predicate values. This expression may only appear on
968 the RHS of assignments.
970 Given X = ASSERT_EXPR <Y, EXPR>, the optimizers can infer
971 two things:
973 1- X is a copy of Y.
974 2- EXPR is a conditional expression and is known to be true.
976 Valid and to be expected forms of conditional expressions are
977 valid GIMPLE conditional expressions (as defined by is_gimple_condexpr)
978 and conditional expressions with the first operand being a
979 PLUS_EXPR with a variable possibly wrapped in a NOP_EXPR first
980 operand and an integer constant second operand.
982 The type of the expression is the same as Y. */
983 DEFTREECODE (ASSERT_EXPR, "assert_expr", tcc_expression, 2)
985 /* Base class information. Holds information about a class as a
986 baseclass of itself or another class. */
987 DEFTREECODE (TREE_BINFO, "tree_binfo", tcc_exceptional, 0)
989 /* Records the size for an expression of variable size type. This is
990 for use in contexts in which we are accessing the entire object,
991 such as for a function call, or block copy.
992 Operand 0 is the real expression.
993 Operand 1 is the size of the type in the expression. */
994 DEFTREECODE (WITH_SIZE_EXPR, "with_size_expr", tcc_expression, 2)
996 /* Extract elements from two input vectors Operand 0 and Operand 1
997 size VS, according to the offset OFF defined by Operand 2 as
998 follows:
999 If OFF > 0, the last VS - OFF elements of vector OP0 are concatenated to
1000 the first OFF elements of the vector OP1.
1001 If OFF == 0, then the returned vector is OP1.
1002 On different targets OFF may take different forms; It can be an address, in
1003 which case its low log2(VS)-1 bits define the offset, or it can be a mask
1004 generated by the builtin targetm.vectorize.mask_for_load_builtin_decl. */
1005 DEFTREECODE (REALIGN_LOAD_EXPR, "realign_load", tcc_expression, 3)
1007 /* Low-level memory addressing. Operands are BASE (address of static or
1008 global variable or register), OFFSET (integer constant),
1009 INDEX (register), STEP (integer constant), INDEX2 (register),
1010 The corresponding address is BASE + STEP * INDEX + INDEX2 + OFFSET.
1011 Only variations and values valid on the target are allowed.
1013 The type of STEP, INDEX and INDEX2 is sizetype.
1015 The type of BASE is a pointer type. If BASE is not an address of
1016 a static or global variable INDEX2 will be NULL.
1018 The type of OFFSET is a pointer type and determines TBAA the same as
1019 the constant offset operand in MEM_REF. */
1021 DEFTREECODE (TARGET_MEM_REF, "target_mem_ref", tcc_reference, 5)
1023 /* Memory addressing. Operands are a pointer and a tree constant integer
1024 byte offset of the pointer type that when dereferenced yields the
1025 type of the base object the pointer points into and which is used for
1026 TBAA purposes.
1027 The type of the MEM_REF is the type the bytes at the memory location
1028 are interpreted as.
1029 MEM_REF <p, c> is equivalent to ((typeof(c))p)->x... where x... is a
1030 chain of component references offsetting p by c. */
1031 DEFTREECODE (MEM_REF, "mem_ref", tcc_reference, 2)
1033 /* The ordering of the codes between OMP_PARALLEL and OMP_CRITICAL is
1034 exposed to TREE_RANGE_CHECK. */
1035 /* OpenMP - #pragma omp parallel [clause1 ... clauseN]
1036 Operand 0: OMP_PARALLEL_BODY: Code to be executed by all threads.
1037 Operand 1: OMP_PARALLEL_CLAUSES: List of clauses. */
1039 DEFTREECODE (OMP_PARALLEL, "omp_parallel", tcc_statement, 2)
1041 /* OpenMP - #pragma omp task [clause1 ... clauseN]
1042 Operand 0: OMP_TASK_BODY: Code to be executed by all threads.
1043 Operand 1: OMP_TASK_CLAUSES: List of clauses. */
1045 DEFTREECODE (OMP_TASK, "omp_task", tcc_statement, 2)
1047 /* OpenMP - #pragma omp for [clause1 ... clauseN]
1048 Operand 0: OMP_FOR_BODY: Loop body.
1049 Operand 1: OMP_FOR_CLAUSES: List of clauses.
1050 Operand 2: OMP_FOR_INIT: Initialization code of the form
1051 VAR = N1.
1052 Operand 3: OMP_FOR_COND: Loop conditional expression of the form
1053 VAR { <, >, <=, >= } N2.
1054 Operand 4: OMP_FOR_INCR: Loop index increment of the form
1055 VAR { +=, -= } INCR.
1056 Operand 5: OMP_FOR_PRE_BODY: Filled by the gimplifier with things
1057 from INIT, COND, and INCR that are technically part of the
1058 OMP_FOR structured block, but are evaluated before the loop
1059 body begins.
1061 VAR must be an integer or pointer variable, which is implicitly thread
1062 private. N1, N2 and INCR are required to be loop invariant integer
1063 expressions that are evaluated without any synchronization.
1064 The evaluation order, frequency of evaluation and side-effects are
1065 unspecified by the standard. */
1066 DEFTREECODE (OMP_FOR, "omp_for", tcc_statement, 6)
1068 /* OpenMP - #pragma omp simd [clause1 ... clauseN]
1069 Operands like for OMP_FOR. */
1070 DEFTREECODE (OMP_SIMD, "omp_simd", tcc_statement, 6)
1072 /* Cilk Plus - #pragma simd [clause1 ... clauseN]
1073 Operands like for OMP_FOR. */
1074 DEFTREECODE (CILK_SIMD, "cilk_simd", tcc_statement, 6)
1076 /* Cilk Plus - _Cilk_for (..)
1077 Operands like for OMP_FOR. */
1078 DEFTREECODE (CILK_FOR, "cilk_for", tcc_statement, 6)
1080 /* OpenMP - #pragma omp distribute [clause1 ... clauseN]
1081 Operands like for OMP_FOR. */
1082 DEFTREECODE (OMP_DISTRIBUTE, "omp_distribute", tcc_statement, 6)
1084 /* OpenMP - #pragma omp teams [clause1 ... clauseN]
1085 Operand 0: OMP_TEAMS_BODY: Teams body.
1086 Operand 1: OMP_TEAMS_CLAUSES: List of clauses. */
1087 DEFTREECODE (OMP_TEAMS, "omp_teams", tcc_statement, 2)
1089 /* OpenMP - #pragma omp target data [clause1 ... clauseN]
1090 Operand 0: OMP_TARGET_DATA_BODY: Target data construct body.
1091 Operand 1: OMP_TARGET_DATA_CLAUSES: List of clauses. */
1092 DEFTREECODE (OMP_TARGET_DATA, "omp_target_data", tcc_statement, 2)
1094 /* OpenMP - #pragma omp target [clause1 ... clauseN]
1095 Operand 0: OMP_TARGET_BODY: Target construct body.
1096 Operand 1: OMP_TARGET_CLAUSES: List of clauses. */
1097 DEFTREECODE (OMP_TARGET, "omp_target", tcc_statement, 2)
1099 /* OpenMP - #pragma omp sections [clause1 ... clauseN]
1100 Operand 0: OMP_SECTIONS_BODY: Sections body.
1101 Operand 1: OMP_SECTIONS_CLAUSES: List of clauses. */
1102 DEFTREECODE (OMP_SECTIONS, "omp_sections", tcc_statement, 2)
1104 /* OpenMP - #pragma omp single
1105 Operand 0: OMP_SINGLE_BODY: Single section body.
1106 Operand 1: OMP_SINGLE_CLAUSES: List of clauses. */
1107 DEFTREECODE (OMP_SINGLE, "omp_single", tcc_statement, 2)
1109 /* OpenMP - #pragma omp section
1110 Operand 0: OMP_SECTION_BODY: Section body. */
1111 DEFTREECODE (OMP_SECTION, "omp_section", tcc_statement, 1)
1113 /* OpenMP - #pragma omp master
1114 Operand 0: OMP_MASTER_BODY: Master section body. */
1115 DEFTREECODE (OMP_MASTER, "omp_master", tcc_statement, 1)
1117 /* OpenMP - #pragma omp taskgroup
1118 Operand 0: OMP_TASKGROUP_BODY: Taskgroup body. */
1119 DEFTREECODE (OMP_TASKGROUP, "omp_taskgroup", tcc_statement, 1)
1121 /* OpenMP - #pragma omp ordered
1122 Operand 0: OMP_ORDERED_BODY: Master section body. */
1123 DEFTREECODE (OMP_ORDERED, "omp_ordered", tcc_statement, 1)
1125 /* OpenMP - #pragma omp critical [name]
1126 Operand 0: OMP_CRITICAL_BODY: Critical section body.
1127 Operand 1: OMP_CRITICAL_NAME: Identifier for critical section. */
1128 DEFTREECODE (OMP_CRITICAL, "omp_critical", tcc_statement, 2)
1130 /* OpenMP - #pragma omp target update [clause1 ... clauseN]
1131 Operand 0: OMP_TARGET_UPDATE_CLAUSES: List of clauses. */
1132 DEFTREECODE (OMP_TARGET_UPDATE, "omp_target_update", tcc_statement, 1)
1134 /* OMP_ATOMIC through OMP_ATOMIC_CAPTURE_NEW must be consecutive,
1135 or OMP_ATOMIC_SEQ_CST needs adjusting. */
1137 /* OpenMP - #pragma omp atomic
1138 Operand 0: The address at which the atomic operation is to be performed.
1139 This address should be stabilized with save_expr.
1140 Operand 1: The expression to evaluate. When the old value of the object
1141 at the address is used in the expression, it should appear as if
1142 build_fold_indirect_ref of the address. */
1143 DEFTREECODE (OMP_ATOMIC, "omp_atomic", tcc_statement, 2)
1145 /* OpenMP - #pragma omp atomic read
1146 Operand 0: The address at which the atomic operation is to be performed.
1147 This address should be stabilized with save_expr. */
1148 DEFTREECODE (OMP_ATOMIC_READ, "omp_atomic_read", tcc_statement, 1)
1150 /* OpenMP - #pragma omp atomic capture
1151 Operand 0: The address at which the atomic operation is to be performed.
1152 This address should be stabilized with save_expr.
1153 Operand 1: The expression to evaluate. When the old value of the object
1154 at the address is used in the expression, it should appear as if
1155 build_fold_indirect_ref of the address.
1156 OMP_ATOMIC_CAPTURE_OLD returns the old memory content,
1157 OMP_ATOMIC_CAPTURE_NEW the new value. */
1158 DEFTREECODE (OMP_ATOMIC_CAPTURE_OLD, "omp_atomic_capture_old", tcc_statement, 2)
1159 DEFTREECODE (OMP_ATOMIC_CAPTURE_NEW, "omp_atomic_capture_new", tcc_statement, 2)
1161 /* OpenMP clauses. */
1162 DEFTREECODE (OMP_CLAUSE, "omp_clause", tcc_exceptional, 0)
1164 /* TRANSACTION_EXPR tree code.
1165 Operand 0: BODY: contains body of the transaction. */
1166 DEFTREECODE (TRANSACTION_EXPR, "transaction_expr", tcc_expression, 1)
1168 /* Reduction operations.
1169 Operations that take a vector of elements and "reduce" it to a scalar
1170 result (e.g. summing the elements of the vector, finding the minimum over
1171 the vector elements, etc).
1172 Operand 0 is a vector.
1173 The expression returns a scalar, with type the same as the elements of the
1174 vector, holding the result of the reduction of all elements of the operand.
1176 DEFTREECODE (REDUC_MAX_EXPR, "reduc_max_expr", tcc_unary, 1)
1177 DEFTREECODE (REDUC_MIN_EXPR, "reduc_min_expr", tcc_unary, 1)
1178 DEFTREECODE (REDUC_PLUS_EXPR, "reduc_plus_expr", tcc_unary, 1)
1180 /* Widening dot-product.
1181 The first two arguments are of type t1.
1182 The third argument and the result are of type t2, such that t2 is at least
1183 twice the size of t1. DOT_PROD_EXPR(arg1,arg2,arg3) is equivalent to:
1184 tmp = WIDEN_MULT_EXPR(arg1, arg2);
1185 arg3 = PLUS_EXPR (tmp, arg3);
1187 tmp = WIDEN_MULT_EXPR(arg1, arg2);
1188 arg3 = WIDEN_SUM_EXPR (tmp, arg3); */
1189 DEFTREECODE (DOT_PROD_EXPR, "dot_prod_expr", tcc_expression, 3)
1191 /* Widening summation.
1192 The first argument is of type t1.
1193 The second argument is of type t2, such that t2 is at least twice
1194 the size of t1. The type of the entire expression is also t2.
1195 WIDEN_SUM_EXPR is equivalent to first widening (promoting)
1196 the first argument from type t1 to type t2, and then summing it
1197 with the second argument. */
1198 DEFTREECODE (WIDEN_SUM_EXPR, "widen_sum_expr", tcc_binary, 2)
1200 /* Widening sad (sum of absolute differences).
1201 The first two arguments are of type t1 which should be integer.
1202 The third argument and the result are of type t2, such that t2 is at least
1203 twice the size of t1. Like DOT_PROD_EXPR, SAD_EXPR (arg1,arg2,arg3) is
1204 equivalent to (note we don't have WIDEN_MINUS_EXPR now, but we assume its
1205 behavior is similar to WIDEN_SUM_EXPR):
1206 tmp = WIDEN_MINUS_EXPR (arg1, arg2)
1207 tmp2 = ABS_EXPR (tmp)
1208 arg3 = PLUS_EXPR (tmp2, arg3)
1210 tmp = WIDEN_MINUS_EXPR (arg1, arg2)
1211 tmp2 = ABS_EXPR (tmp)
1212 arg3 = WIDEN_SUM_EXPR (tmp2, arg3)
1214 DEFTREECODE (SAD_EXPR, "sad_expr", tcc_expression, 3)
1216 /* Widening multiplication.
1217 The two arguments are of type t1.
1218 The result is of type t2, such that t2 is at least twice
1219 the size of t1. WIDEN_MULT_EXPR is equivalent to first widening (promoting)
1220 the arguments from type t1 to type t2, and then multiplying them. */
1221 DEFTREECODE (WIDEN_MULT_EXPR, "widen_mult_expr", tcc_binary, 2)
1223 /* Widening multiply-accumulate.
1224 The first two arguments are of type t1.
1225 The third argument and the result are of type t2, such as t2 is at least
1226 twice the size of t1. t1 and t2 must be integral or fixed-point types.
1227 The expression is equivalent to a WIDEN_MULT_EXPR operation
1228 of the first two operands followed by an add or subtract of the third
1229 operand. */
1230 DEFTREECODE (WIDEN_MULT_PLUS_EXPR, "widen_mult_plus_expr", tcc_expression, 3)
1231 /* This is like the above, except in the final expression the multiply result
1232 is subtracted from t3. */
1233 DEFTREECODE (WIDEN_MULT_MINUS_EXPR, "widen_mult_minus_expr", tcc_expression, 3)
1235 /* Widening shift left.
1236 The first operand is of type t1.
1237 The second operand is the number of bits to shift by; it need not be the
1238 same type as the first operand and result.
1239 Note that the result is undefined if the second operand is larger
1240 than or equal to the first operand's type size.
1241 The type of the entire expression is t2, such that t2 is at least twice
1242 the size of t1.
1243 WIDEN_LSHIFT_EXPR is equivalent to first widening (promoting)
1244 the first argument from type t1 to type t2, and then shifting it
1245 by the second argument. */
1246 DEFTREECODE (WIDEN_LSHIFT_EXPR, "widen_lshift_expr", tcc_binary, 2)
1248 /* Fused multiply-add.
1249 All operands and the result are of the same type. No intermediate
1250 rounding is performed after multiplying operand one with operand two
1251 before adding operand three. */
1252 DEFTREECODE (FMA_EXPR, "fma_expr", tcc_expression, 3)
1254 /* Widening vector multiplication.
1255 The two operands are vectors with N elements of size S. Multiplying the
1256 elements of the two vectors will result in N products of size 2*S.
1257 VEC_WIDEN_MULT_HI_EXPR computes the N/2 high products.
1258 VEC_WIDEN_MULT_LO_EXPR computes the N/2 low products. */
1259 DEFTREECODE (VEC_WIDEN_MULT_HI_EXPR, "widen_mult_hi_expr", tcc_binary, 2)
1260 DEFTREECODE (VEC_WIDEN_MULT_LO_EXPR, "widen_mult_lo_expr", tcc_binary, 2)
1262 /* Similarly, but return the even or odd N/2 products. */
1263 DEFTREECODE (VEC_WIDEN_MULT_EVEN_EXPR, "widen_mult_even_expr", tcc_binary, 2)
1264 DEFTREECODE (VEC_WIDEN_MULT_ODD_EXPR, "widen_mult_odd_expr", tcc_binary, 2)
1266 /* Unpack (extract and promote/widen) the high/low elements of the input
1267 vector into the output vector. The input vector has twice as many
1268 elements as the output vector, that are half the size of the elements
1269 of the output vector. This is used to support type promotion. */
1270 DEFTREECODE (VEC_UNPACK_HI_EXPR, "vec_unpack_hi_expr", tcc_unary, 1)
1271 DEFTREECODE (VEC_UNPACK_LO_EXPR, "vec_unpack_lo_expr", tcc_unary, 1)
1273 /* Unpack (extract) the high/low elements of the input vector, convert
1274 fixed point values to floating point and widen elements into the
1275 output vector. The input vector has twice as many elements as the output
1276 vector, that are half the size of the elements of the output vector. */
1277 DEFTREECODE (VEC_UNPACK_FLOAT_HI_EXPR, "vec_unpack_float_hi_expr", tcc_unary, 1)
1278 DEFTREECODE (VEC_UNPACK_FLOAT_LO_EXPR, "vec_unpack_float_lo_expr", tcc_unary, 1)
1280 /* Pack (demote/narrow and merge) the elements of the two input vectors
1281 into the output vector using truncation/saturation.
1282 The elements of the input vectors are twice the size of the elements of the
1283 output vector. This is used to support type demotion. */
1284 DEFTREECODE (VEC_PACK_TRUNC_EXPR, "vec_pack_trunc_expr", tcc_binary, 2)
1285 DEFTREECODE (VEC_PACK_SAT_EXPR, "vec_pack_sat_expr", tcc_binary, 2)
1287 /* Convert floating point values of the two input vectors to integer
1288 and pack (narrow and merge) the elements into the output vector. The
1289 elements of the input vector are twice the size of the elements of
1290 the output vector. */
1291 DEFTREECODE (VEC_PACK_FIX_TRUNC_EXPR, "vec_pack_fix_trunc_expr", tcc_binary, 2)
1293 /* Widening vector shift left in bits.
1294 Operand 0 is a vector to be shifted with N elements of size S.
1295 Operand 1 is an integer shift amount in bits.
1296 The result of the operation is N elements of size 2*S.
1297 VEC_WIDEN_LSHIFT_HI_EXPR computes the N/2 high results.
1298 VEC_WIDEN_LSHIFT_LO_EXPR computes the N/2 low results.
1300 DEFTREECODE (VEC_WIDEN_LSHIFT_HI_EXPR, "widen_lshift_hi_expr", tcc_binary, 2)
1301 DEFTREECODE (VEC_WIDEN_LSHIFT_LO_EXPR, "widen_lshift_lo_expr", tcc_binary, 2)
1303 /* PREDICT_EXPR. Specify hint for branch prediction. The
1304 PREDICT_EXPR_PREDICTOR specify predictor and PREDICT_EXPR_OUTCOME the
1305 outcome (0 for not taken and 1 for taken). Once the profile is guessed
1306 all conditional branches leading to execution paths executing the
1307 PREDICT_EXPR will get predicted by the specified predictor. */
1308 DEFTREECODE (PREDICT_EXPR, "predict_expr", tcc_expression, 1)
1310 /* OPTIMIZATION_NODE. Node to store the optimization options. */
1311 DEFTREECODE (OPTIMIZATION_NODE, "optimization_node", tcc_exceptional, 0)
1313 /* TARGET_OPTION_NODE. Node to store the target specific options. */
1314 DEFTREECODE (TARGET_OPTION_NODE, "target_option_node", tcc_exceptional, 0)
1316 /* ANNOTATE_EXPR.
1317 Operand 0 is the expression to be annotated.
1318 Operand 1 is the annotation kind. */
1319 DEFTREECODE (ANNOTATE_EXPR, "annotate_expr", tcc_expression, 2)
1321 /* Cilk spawn statement
1322 Operand 0 is the CALL_EXPR. */
1323 DEFTREECODE (CILK_SPAWN_STMT, "cilk_spawn_stmt", tcc_statement, 1)
1325 /* Cilk Sync statement: Does not have any operands. */
1326 DEFTREECODE (CILK_SYNC_STMT, "cilk_sync_stmt", tcc_statement, 0)
1329 Local variables:
1330 mode:c
1331 End: